Further Explanation multiple representation


#1

So, I’m liking this unit. I think it’s great information for the students. I’ve been getting questions I really don’t know the answer to. I get that all this information is being sent to the computer using binary. When it comes to this Combining Representations lesson I see how the information has to be designated as numbers, letters, images, sounds, etc. I’d like to understand more about how we tell the computer what type of information it will be and how we show the computer that we will have these different types of information that we show in this lesson and in 5.8.
I hope this makes sense and maybe it’s just too confusing of a topic to explain to the kids but they are wondering about it.


#2

Hi Chris,

Here is a Code.org video explaining “How Computers Work: Binary & Data”

Hope this helps,
Karen


#3

Thanks Karen, This is a good video for the different types of data. I’m still a bit confused by how a computer knows if the binary data it is getting is a number, a letter, an image, etc. This seems to be an important part of the idea of multiple representation. I don’t know if I’m explaining this well.


#4

Chris,

That really has to do with the program in which you are programming. Computers actually speak in machine code, which we can’t begin to understand. The IDE (Integrated Developers Environment) is programmed to take whatever the user types in and makes (compiles) it into a language that the machine can understand and then can communicate with other machines/computers if needed. There are multiple levels of abstraction that get a lot more complicated as you get closer to the CPU. I don’t fully understand it either but some helpful guides have been the book Code and this EdX course. That students with similar questions have explored.

Hope that helps,
Brad


#5

Thanks Brad. I’m not sure exactly how I can explain it to middle school kids. I guess it comes down to the idea that the different types of data we learn about in the first part of this unit are the very basics of how data gets into the computer which is great for the kids to know, but they’ll really never have to deal with data on this level.
I will look into the resources you suggested.

Thanks


#6

It’s great that your students are asking such insightful questions!

One thing your kids might want to think about is file type. Data on the computer is stored in files, and every file has a different system for storing information, just like our pet record did. We knew that the first 8 bits would be a number and the next 8 bits would be a letter because that’s how we defined our file. We could define a different file to interpret the first 8 bits as a number and the second 8 bits as a letter.

You can force your computer to interpret a a file in a wrong way. For example, you could open up an image in TextEdit (Mac) or Notepad (Windows) and look at the text interpretation of those same bits. That’s why it’s so important for a computer program to know how to interpret a file. For some programs, if they aren’t programmed with the file type and don’t have any way to know how to interpret the bits, they won’t even try, and you will get an error. Other programs, such as Notepad or TextEdit, will usually try to do their best, even when it is obviously not a text file.

Elizabeth


#7

Thanks Elizabeth, I like this way of looking at it. I definitely see a lot of examples in certain image types like opening an image from an iphone in certain other programs or a photoshop file. I might even show some of these examples to the kids.

Thanks!